Free Nutrition & Diet Calculators

Calculate chemical dosages, equipment sizing, water volume, and operating costs for your health — all for free. No signup, no guesswork.

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Body Metrics

BMI, body fat percentage, TDEE, BMR, ideal weight, waist-to-hip ratio, lean body mass, and metabolic age calculators.

8 calculators

Macros & Calories

Macro split, calorie deficit, protein intake, carb cycling, keto macros, calorie burn, net carbs, and cheat day impact calculators.

8 calculators

Diet Planning

Meal prep portions, water intake, fiber intake, sodium tracker, intermittent fasting, food swap, and calorie density calculators.

7 calculators

Vitamins & Minerals

Vitamin D dosage, iron intake, calcium needs, omega-3, electrolyte, supplement cost, and daily value percentage calculators.

7 calculators

Popular Calculators

BMI Calculator

Calculate your Body Mass Index (BMI) based on weight and height to assess whether you are underweight, normal weight, overweight, or obese.

body-metrics

Body Fat Percentage Calculator

Estimate your body fat percentage using the U.S. Navy circumference method based on waist, neck, and height measurements.

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TDEE Calculator

Calculate your Total Daily Energy Expenditure (TDEE) to understand how many calories you burn each day based on your activity level.

body-metrics

Ideal Weight Calculator

Find your ideal body weight using four established formulas: Devine, Robinson, Miller, and Hamwi, with frame size adjustment.

body-metrics

Macro Calculator

Calculate your daily macronutrient targets based on your body stats, activity level, and fitness goal.

macros-calories

Calorie Deficit Calculator

Calculate the daily calorie deficit needed to reach your goal weight in a target timeframe.

macros-calories

Protein Intake Calculator

Calculate your optimal daily protein intake based on body weight, activity level, and fitness goal.

macros-calories

Keto Macro Calculator

Calculate your ketogenic diet macros with the standard 70% fat, 25% protein, 5% carb split.

macros-calories

Meal Prep Portions Calculator

Calculate per-meal macronutrient portions and total weekly prep quantities based on your calorie target and macro split.

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Water Intake Calculator

Estimate your optimal daily water intake based on body weight, exercise, climate, and caffeine consumption.

diet-planning

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